GCN Circular 3744
Subject
GRB050802: CrAO optical observations
Date
2005-08-03T11:02:17Z (19 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Pavlenko, Yu. Efimov, A. Shlyapnikov, A. Baklanov(CrAO), A.Pozanenko
(IKI), M. Ibrahimov (MAO) on behalf of larger GRB follow up collaboration
report:
We observed the error box of GRB050802 (Band et al., GCN 3734) with 2.6m
Shain telescope (CrAO) on August 2 between (UT) 18:46 - 20:40. OT found by
McGowan et al. (GCN 3739) is clearly detected. Preliminary VRI photometry is
following:
Mean time Exposure Filter Magnitude
(UT) s
18:54 60 V 20.6
20:27 2x60 V 21.1
18:48 60 R 20.6
20:36 2x60 R 21.0
18:56 60 I 20.2
20:39 2x60 I 20.6
with a typical error of 0.1m.
Comparing decay index of fading light curve in V between magnitudes obtained
in UVOT observation (McGowan et al. GCN 3739) and our first observation in
18:54, and decay index obtained based on our observations we suggest that
the break of OT light curve occurs between (UT) 19:00 - 20:40. Detailed
analysis is underway.
Finding chart of the OT in V band can be found in
http://grb.rssi.ru/GRB050902.
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